Answer:
81/256
Explanation:
By doing a test cross of albinism and sickle cell anemia you'll see that the probability that one child is unaffected by either conditions will be 9/16. Both children would be 9/16 * 9/16.
Since fraternal twins are developed from two separate fertilization events the probability chance will be independent.
Primary reinforcers have distinctive reinforcing qualities; not learned. In addition, secondary reinforcers has no inherent value and only has reinforcing qualities when linked with a primary reinforcers. The positive reinforcement is a desirable stimulus is added to increase behavior while negative reinforcement is an undesirable stimulus is removed to increase behavior.
<span>The environment has a greater amount of long nectar tubed flowers and short nectar tubed flowers causing disruptive selection in medium bill length birds.
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